Rhododendrons, Hilliers Arboretum, Romsey, Hampshire, England, UK. Stock Photo

Rhododendrons, Hilliers Arboretum, Romsey, Hampshire, England, UK. Rhododendron, genus Rhododendron, diverse genus of about 1,000 species of woody flowering plants in the heath family Ericaceae, notable for their attractive flowers and handsome foliage. Rhododendrons are native chiefly in the north temperate zone, especially in the moist acidic soil of the Himalayas and into Southeast Asia to the mountains of New Guinea. A number of species are cultivated as ornamentals.